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Biomedical subjects

Y Honma

Publications and source records attributed to Y Honma.

At least 91 records · Page 5Linked to original sources
PubMed1998

Enhancement by bufalin of retinoic acid-induced differentiation of acute promyelocytic leukemia cells in primary culture.

Bufalin, a cardiotonic steroid isolated from the Chinese toad venom preparation Chan'su, has differentiation-inducing activity in several myeloid leukemia cell lines. We examined the effect of bufalin on differentiation of leukemic cells from acute myeloid leukemia (AML) patients in primary culture. Bufalin significantly stimulated functional and morphologic differentiation of leukemia cells in four of 20 cases, suggesting that bufalin alone is only a modest inducer of differentiation of AML cells in primary culture. In contrast, acute promyelocytic leukemia (APL) cells showed synergistic differentiation after treatment with all-trans retinoic acid (RA) and bufalin. In some cases, bufalin restored RA sensitivity to previously resistant APL cells. The effective concentration of bufalin for differentiation-inducing activity in APL cells was lower than for its cardiac action. Combined treatment with bufalin and RA may be more effective than RA alone in differentiation therapy of APL.

Acute Disease↗
PubMed1998

Induction of differentiation of myelogenous leukemia cells by humulone, a bitter in the hop.

The active form of vitamin D, 1alpha,25-dihydroxyvitamin D3 (VD3), inhibits proliferation and induces differentiation of myelomonocytic leukemia cells, but its clinical use is limited by the adverse effect of hypercalcemia. VD3 mobilizes calcium stores from bone by inducing the dissolution of bone mineral and matrix. We have recently found that humulone, a bitter in the hop extract for beer brewing, effectively inhibits bone resorption. In this study we examined the effect of humulone on the differentiation of human myelogenous leukemia cells. Humulone alone inhibited the growth of monoblastic leukemia U937 cells while only slightly increasing differentiation markers such as nitroblue tetrazolium (NBT)-reducing and lysozyme activities. Humulone effectively enhanced the differentiation-inducing action of VD3. Other myelomonocytic leukemia cells were induced to differentiate by VD3 and this was also enhanced by humulone. Since humulone is a less-toxic inhibitor of bone resorption, the combination of humulone and VD3 may be useful in differentiation therapy of myelomonocytic leukemia.

Anti-Infective Agents↗
PubMed1998

Elevated expression of differentiation inhibitory factor nm23 mRNA in monoblastic crisis of a patient with chronic myelogenous leukemia.

Differentiation inhibitory factor nm23 gene has been found to be expressed in high quantities in acute myelogenous leukemia (AML), especially in acute monocytic leukemia (AML-M5) and is suggested as a new prognostic factor in AML-M5. We report an example of elevated expression of nm23 mRNA in a patient with chronic myelogenous leukemia (CML) who developed monoblastic crisis. Relative levels of nm23-H1 and -H2 mRNA extracted from the patient's peripheral blood mononuclear cells and bone marrow mononuclear cells were measured by quantitative reverse transcriptase polymerase chain reaction. The level of nm23-H1 mRNA in CML cells at the chronic phase was as high as that in bone marrow cells from healthy volunteers. The mRNA level of nm23-H2 was slightly below the normal level. At blastic crisis, however, expression of both nm23-H1 and -H2 mRNA was elevated to about three to nine times of that at the chronic phase. Proliferated blastic cells were positive for non-specific esterase, and the serum lysozyme level was elevated and diagnosed as monoblastic crisis. The patient received combined chemotherapy but response was partial. These findings are compatible with our previous report that nm23 gene is overexpressed in monocytic leukemia.

Antigens, Neoplasm↗
PubMed1998

Combined analysis of differentiation inhibitory factor nm23-H1 and nm23-H2 as prognostic factors in acute myeloid leukaemia.

Differentiation inhibitory factor (nm23 protein) inhibited the induction of the differentiation of various leukaemic cell lines. We previously reported that nm23 genes (H1 and H2) were overexpressed in acute myelogenous leukaemia (AML) and nm23-H1 expression predicted the prognosis of AML, especially AML-M5. To clarify the correlation between French-American-British (FAB) classification and nm23 expression level and to clarify the involvement of nm23-H2 and nm23-H1 in patient survival, we investigated the relative levels of nm23-H1 and -H2 mRNA in 76 AML samples using the reverse transcriptase-polymerase chain reaction. We confirmed that the expression of both nm23-H1 and -H2 genes in AML samples from three different hospitals was significantly higher than that in normal blood cells (P < 0.0005). Overexpression of nm23-H1 was observed in each FAB AML-M1, -M2, -M3, -M4 or -M5 subtype, and the predictive effect of nm23-H1 expression on AML prognosis was shown in FAB AML-M2 and -M5 cases. Although overexpression of nm23-H2 was also found in each FAB subtype, the expression of nm23-H2 in AML-M1 and -M3 cells was not significantly higher than that in normal cells. Among AML subtypes, AML-M3 showed the lowest expression levels of both nm23 genes. To understand the relationship between nm23-H1 and -H2 expression levels, nm23 expression levels for all the AML cases were plotted and divided into four groups (group A, nm23-H1 and -H2 both high; B, both low; C, only nm23-H1 high; D, only nm23-H2 high). A statistically significant correlation between the levels of expression of nm23-H1 and -H2 was observed (r= 0.726). Most AML-M3 cases belonged to group B, but not other types of AML. Analysis of survival probability between the groups showed that group B survived for significantly longer compared with group A. Furthermore, AML-M3 cases survived for significantly longer compared with non-M3 cases in the same group B. These data suggest that low expression levels of both nm23-H1 and -H2 are associated with good prognosis in AML patients.

Acute Disease↗
PubMed1998

Growth inhibition and differentiation induction in human monoblastic leukaemia cells by 1alpha-hydroxyvitamin D derivatives and their enhancement by combination with hydroxyurea.

The active form of vitamin D, 1alpha,25-dihydroxyvitamin D3 (1,25(OH)2D3), is a potent inducer of differentiation in myeloid leukaemia cells, but its clinical use is limited because of its hypercalcaemic activity. We examined the ability of 1,25(OH)2D3 in combination with several anti-cancer drugs to inhibit the proliferation of, and induce differentiation in, human monoblastic leukaemia U937 cells. Hydroxyurea (HU), cytarabine and camptothecin showed effective synergism with 1,25(OH)2D3 with regard to growth inhibition, while daunorubicin and etoposide had only modest synergistic effects. HU and cytarabine effectively enhanced nitroblue tetrazolium-reducing activity induced by 1,25(OH)2D3. HU also enhanced the morphological maturation and expression of CD11b and CD14 in cells treated with 1,25(OH)2D3. Among the anti-cancer drugs examined, HU had the greatest synergistic effects with 1,25(OH)2D3 with regard to growth inhibition and differentiation induction in U937 cells. HU also enhanced the differentiation of other myeloid leukaemia HL-60, ML-1, THP-1, P39/TSU, P31/FUJ and NB4 cells induced by 1,25(OH)2D3 and that of U937 cells induced by 24-epi-1,25(OH)2D2 and 1,25(OH)2D7. Interestingly, 1alpha(OH)D derivatives (1alpha-hydroxyvitamin D3, D2, D4 and D7) effectively induced the differentiation of monoblastic leukaemia U937, P39/TSU and P31/FUJ cells. HU also enhanced the growth inhibition and differentiation of U937 cells induced by 1alpha(OH)D derivatives. As 1alpha(OH)D derivatives preferentially act on monocytic cells, they may be useful in the treatment of acute monocytic leukaemia, both alone and in combination with HU.

Antineoplastic Agents↗
PubMed1998

Lower risks of adverse outcome in twins conceived by artificial reproductive techniques compared with spontaneously conceived twins.

The outcomes of twins conceived by 136 women after medical assistance (MA) such as ovulation induction with or without assisted reproductive techniques, and twins conceived spontaneously (SP) by 72 women were compared. All 208 women were monitored from < 20 weeks gestation; they all delivered at > or = 24 weeks gestation. The chorionicity of the placenta was diagnosed antenatally and confirmed after delivery. There were 10 perinatal deaths; the physical and neurological status of the remaining 406 infants was assessed at 1 year of corrected age. There were no differences in gestational age at birth, the birth weights of the larger and smaller twins, the birth weight discordance, or the incidence of life-threatening major malformations between groups. Adverse infant outcomes, such as death, cerebral palsy and mental retardation occurred in nine (3.3%) of 272 MA twins compared with 12 (8.3%) of 144 SP twins (P < 0.05). The placenta was monochorionic in only three (2.2%) of 136 MA twin pregnancies compared with 41 (57%) of 72 SP twin pregnancies (P < 0.001). Of the 21 infants with adverse outcomes, nine had monochorionic placentas. Thus, the risk of an adverse outcome was 2.8-fold higher (95% confidence interval (CI) 1.2-6.4) in monochorionic twins than in dichorionic twins (10 versus 3.7%; P < 0.05). There was no difference in the incidence of adverse infant outcomes between SP (4.8%) and MA (3.4%) twins with dichorionic placentas. These findings suggest that ovulation induction in itself was not associated with an adverse outcome of twin pregnancies. The lower frequency of monochorionic placentas in MA twins may have been responsible for the lower risk of an adverse outcome in MA twins.

Birth Weight↗
PubMed1998

Adhesive property of toxin-coregulated pilus of Vibrio cholerae O1.

The adhesive property of toxin-coregulated pilus (TCP) to the human intestine jejunum), and whether or not TCP mediates the adhesion of Vibrio cholerae 395 organisms to the intestinal epithelium were investigated using visually proving methods. The purified TCP did not agglutinate human erythrocytes nor adhere to the surface of human intestinal epithelium. V. cholerae 395 adhered to the epithelium, but the adhesion was not inhibited by blocking the pili with the Fab fraction of anti-TCP IgG. The organisms adhered to the intestine treated with purified TCP in advance, as well as to the intact intestine. These findings suggest that TCP is not involved in the adhesion of these organisms to the intestinal epithelium.

Adhesins, Bacterial↗
PubMed1998

Filamentous phage fs1 of Vibrio cholerae O139.

Filamentous phage, fs1, was obtained from Vibrio cholerae O139. The lysogenized strains produced a large amount of fs1 phage in the culture supernatant. This phage was previously reported as novel fimbriae of that organism. The genome of the phage was a 6.5 kb single-stranded DNA. The capsid of fsl consists of a small molecule peptide (about 2.5 kDa).

Capsid↗
PubMed1998

Epidemiologic typing of methicillin-resistant Staphylococcus aureus in neonate intensive care units using pulsed-field gel electrophoresis.

To elucidate the mode of dissemination of methicillin-resistant Staphylococcus aureus (MRSA) in neonate intensive care units (NICUs), a total of 223 isolates from 3 separate hospitals were investigated between 1994 and 1996 by a DNA fingerprinting technique with pulsed-field gel electrophoresis (PFGE). Exoprotein profiles of some strains were also examined using SDS-polyacrylamide gel-electrophoresis (SDS-PAGE) and the assessment of enzyme/toxin production such as coagulase, enterotoxin and TSST-1. Judging from the strain typing data from PFGE results and the epidemiological data, 2 different types of PFGE patterns (A and B) and their subtypes (A', A'' and B') were identified. The A type including A' and A'' (comprising approximately 95% of the isolates) was markedly dominant. Only 5% of the isolates belonged to type B and subtype B'. On the other hand, MRSA isolated from adult patients admitted to the same hospital showed many different PFGE patterns. The results strongly suggested that some strain(s) with specific PFGE pattern(s) is prevalent in NICUs. Furthermore, isolates which expressed the same PFGE pattern did not always express the same SDS-PAGE pattern. There were some isolates with different abilities to produce coagulase, enterotoxin C and toxic-shock syndrome toxin (TSST)-1, and the abilities had no relation with a particular type of PFGE pattern. Therefore, a combination of PFGE analysis and biochemical analyses of coagulase, enterotoxin C and TSST-1 may provide us with more detailed information for the epidemiological study of MRSA in NICUs.

Adult↗
PubMed1998

Relationship between O-serogroup and presence of pathogenic factor genes in Escherichia coli.

A total of 383 isolates of serogroup-based enteropathogenic and enteroinvasive Escherichia coli (310 strains of EPEC and 73 strains of EIEC) were examined for the presence of corresponding pathogenic genes. The serogroup-based EPEC consisted of 232 strains isolated from diarrhea patients and of 78 strains from healthy carriers. The gene encoding intimin, eaeA, was detected in 42 of the 232 EPEC strains from patients (18.1%) and 9 of the 78 strains from carriers (11.5%). The difference was not significant. The bfp gene on the EAF plasmid was detected in 7 of the 42 eaeA-positive EPEC strains from patients but was not detected in the 9 strains from carriers. In serogroup-based EIEC, a chromosomal ipaH gene encoding one of the invasive plasmid antigens was detected in 4 of the 60 strains from patients (6%) but not in the 13 strains from carriers. The 4 ipaH-positive strains possessed the invasive plasmid. These results suggested that the serogroup-based diagnosis of EPEC and EIEC is not sufficient for identifying strains carrying the eaeA or ipaH gene.

Adhesins, Bacterial↗
PubMed1998

Effect of daily vaginal disinfection on duration of gestation after premature rupture of the membranes and on infant outcome.

OBJECTIVES: We examined the effects of daily vaginal disinfection on the interval between premature rupture of the membranes (PROM) and delivery and on infant outcome. METHODS: Daily vaginal disinfection with povidone iodine was performed on 43 women with PROM. The control group consisted of 59 women with PROM who did not undergo vaginal disinfection. In both groups, the infants born to these women were followed until 1 year of corrected age. RESULTS: The degree of cervical dilatation, the leukocyte count, and the serum C-reactive protein level on admission did not differ between the 2 groups. Although there was no difference in the gestational week at delivery between the groups, the interval between PROM and delivery was significantly longer in the disinfectant group than among the control subjects (9.5 +/- 14.9 days vs. 3.9 +/- 5.1 days, p < 0.01). There was no difference in infant outcome between the 2 groups. CONCLUSIONS: These findings suggest that daily vaginal disinfection with povidone iodine prolongs the duration of gestation in women with PROM and dose not have an adverse effect on the fetus.

Adolescent↗
PubMed1998

Difference in outcome of twins between early and delayed referrals.

Data on the prognosis of twins from tertiary institutions may not represent the general incidence of adverse infant outcomes. We retrospectively investigated the infant outcome in 32 twin gestations referred to us at 29.9 +/- 3.7 weeks of gestation (range, 21 to 38 weeks) (late referral group) and 237 twin gestations that had been monitored by us since < 20 weeks' gestation (control group). The physical and neurological status of infants was assessed at 1 year of corrected age. Delivery occurred 3.1 weeks earlier in the late referral group than in the control group (32.4 +/- 3.9 vs 35.5 +/- 2.4 weeks, p < 0.001). Deaths by 1 year of age and disabilities such as cerebral palsy, mental retardation, and epilepsy occurred in 16 (25%) of 64 infants in the late referral group compared with 24 (5.1%) of 474 infants in the control group (p < 0.001). Thus, the inclusion of data on women who were referred late increased the incidence of adverse infant outcomes in our tertiary hospital from 5.1% to 7.4% (40/538). It was not known whether an early referral to a tertiary hospital would have improved the outcome in the late referral group. These findings suggest that data from tertiary institutions on the prognosis of twins may be affected adversely by the inclusion of data on women who are referred because of complications.

Birth Weight↗
PubMed1998

Differentiation inhibitory factor Nm23 as a prognostic factor for acute myeloid leukemia.

The differentiation inhibitory factor nm23 inhibits the differentiation of murine and human myeloid leukemia cells. The inhibition of differentiation may be associated with the aggressive behavior of leukemia. To clarify the role of nm23 in human myeloid leukemia, we investigated the relative levels of nm23-H1, nm23-H2 and c-myc transcripts in bone marrow and blood samples from 110 patients with acute myeloid leukemia (AML) using the reverse transcriptase polymerase chain reaction. The expression levels of nm23-H1 and nm23-H2 in these AML samples were significantly higher than in normal blood cells, and a higher level of nm23-H1 expression was correlated with poor prognosis for AML patients. Analysis of the correlation between nm23 expression and clinical parameters demonstrated that increased nm23-H1 mRNA levels were associated with resistance to initial chemotherapy and reduced overall survival. Multivariate analysis of putative prognostic factors revealed that elevated nm23-H1 mRNA levels significantly influenced the prognosis of patients with AML, particularly in AML-M5.

Acute Disease↗
PubMed1998

A novel uracil analog, 6-chloro-5-(2-propenyl)uracil, preferentially enhances growth inhibition and differentiation of myeloid leukemia cells induced by 1alpha,25-dihydroxyvitamin D3.

The novel uracil analog, 6-chloro-5-(2-propenyl)uracil (TI90), inhibited the growth of myeloid leukemia cells and induced morphologic and functional differentiation of the cells. Although TI90 was a weak inducer of differentiation, it greatly enhanced the growth inhibition and differentiation of the leukemia cells previously induced by 1alpha,25-dihydroxyvitamin D3 (VD3) or all-trans retinoic acid (ATRA). TI90 cooperated with VD3 much more effectively than with ATRA in inhibiting cell growth and inducing differentiation. It also decreased the effective concentration of VD3 to the 10(-10) M level. On the other hand, there was no significant synergy between VD3 and the other uracil analogs. TI90 did not affect VD3 metabolism or the number and affinity of VD3 receptors (VDR) in HL-60 cells. Signals from VD3 are predominantly mediated by VDR and the ligand-activated binding of VDR to vitamin D-responsive element (VDRE) as a heterodimer with the retinoid X receptor (RXR). According to the results of a gel shift assay, TI90 enhanced the intensity of the retarded band with synthetic VDRE oligomer in the presence of VD3, suggesting that TI90 increases the number of phosphorylated receptors by inhibiting phosphatase activity, and also stimulates the formation of a functional complex of VDR with RXR.

Antimetabolites, Antineoplastic↗
PubMed1998

[Active life expectancy, life expectancy and ADL in Japanese elderly].

The purpose of the present Study is to analyze the incidence of loss of active life and death rates over a 36 month period in elderly people living a home, to attempt to determine relationships of index of ADL for bed ridden elderly to incidence and expectancies of active life loss, for life and active life. The definition of loss of activities was as follows: Long term (over six months) medication at home, long term (over six months) admission to hospital or intermediate institute for elderly, admission to nursing home or death. Subjects were 6,883 people living at home in Ogi, Sage prefecture, aged 70 years or older. A total of 6,753 people could be followed up for thirty six months, with 287 people having long term medication at home, 389 people having long term admission in hospital or intermediate institute for elderly, 45 people were admission to nursing home and of these groups defined as experiencing, 490 people were died of all subjects, 746 deaths were observed. The main results were as follows: (1) Annual mortality rate was 5.4% for males, 3.0% for females, and annual rate of active life loss was 7.1% for males, 6.0% for females. Life expectancy for the 70-74 year group was 13.7 years for male, 17.9 years for female, and active life expectancy for the 70-74 year group was 12.0 year for males, 13.9 years for females. The difference between life expectancy and active life expectancy was 1.7 years for male, 4.2 years for female, which can be considered the average length of term requiring care. (2) From the relation between scale of active daily living for the handicapped elderly and the life expectancies of life and active life by Cox proportional hazard model analysis of survival, controlling for age and sex, five categories of classification for active daily living for a handicapped elderly were developed: 1-very healthy with abilities for using transportation (train and bus); 2-abilities of moving in the neighborhood by oneself; 3-abilities of moving in the neighborhood with help; 4-Chair-bound, 5-Bed-bound.

Activities of Daily Living↗
PubMed1997

Molecular analysis of a filamentous phage (fsl) of Vibrio cholerae O139.

A filamentous bacteriophage from Vibrio cholerae O139 strain A1-4450 was isolated (fsl). The phage fsl had a ssDNA genome and dsDNA as a replicative form (RF) in lysogenic host cell. The DNA sequence of fsl RF was determined. It consisted of 6340 bp and had a G + C content of 43.5%. Fifteen possible ORFs were found in fsl. One of them, ORF384, was estimated to encode 384 amino acid residues (44.6 kDa) and had homologous regions with the zot gene of V. cholerae and gene I of the coliphage group. ORF104, located upstream of ORF384, was homologous to gene 93 protein of Pf3 (filamentous phage of Pseudomonas sp.) corresponding to gene VI of coliphage. Other than ORF384 and ORF104, the ORF81, ORF44, ORF29, and ORF193 were speculated to correspond to gene V, gene VII, gene IX, and gene III, respectively, in the order as reported on f1 phage.

Amino Acid Sequence↗